Energy savings and improved security through intelligent lighting systems

ABSTRACT

An intelligent lighting system employs energy efficient outdoor lighting and intelligent sensor technology in cooperation with video analytics processing. The lighting system selectively illuminates outdoor spaces and identifies and evaluates events in a scene monitored by a video camera, thereby to facilitate proactive and appropriate security responses to those events. Selective use of advanced lighting fixtures may significantly reduce costs of lighting areas that are monitored by security systems such as streets, public parks, and parking lots, while simultaneously improving security, safety, and traffic control. Energy savings alone, for a properly designed system, are estimated at 50%-90% of current usage. When combined with remote monitoring, such systems may prevent accidents and criminal activity.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/104,281, filed Apr. 16, 2008, the contents of which is incorporatedherein by reference in its entirety.

COPYRIGHT NOTICE

A portion of the disclosure of this patent document contains materialthat is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in the Patent and TrademarkOffice patent file or records, but otherwise reserves all copyrightrights whatsoever. 37 CFR § 1.71(d).

TECHNICAL FIELD

The system disclosed relates to video analytics technology, outdoorlighting systems, sensors, and security for public and commercialvenues. Video analytics technology entails the use of computer vision,artificial intelligence techniques, and video processing algorithms tofilter video data for the purpose of detecting behavior or events thatwarrant alerting security personnel.

BACKGROUND INFORMATION

In the United States, between 10 and 100 billion kilowatt-hours ofelectric power are used every year to light roads, highways, and parkinglots at night. Airline passengers descending into a city on a clearnight can easily see the extent to which electricity is being used tolight streets and roads throughout the night for the purpose of safetyand security. Much of the time, this energy is being expendedunnecessarily when thoroughfares are untraveled and parking lots arevacant. Not only is the United States wasting a tremendous amount ofelectrical energy by perpetually illuminating empty streets and parkinglots, but extraneous lights also cause “light noise,” a form of lightpollution that has become so extreme that few city dwellers ever seestars, even on a cloudless night. Furthermore, by-products created bythis wasted energy may continue to have a lasting and destructive impacton the environment.

Despite the wasted energy, parking lot security remains insufficient,and nighttime crime continues to pose a serious problem at colleges, incommercial areas, and in public spaces. More than 60% of crime onuniversity campuses is reported to take place in parking lots. Parkinglots are often considered the most dangerous locations for businesscommuters and apartment dwellers (“Campus Communications” and “ParkingProtection,” by john Mesenbrink, Security Magazine, September 2001).Malls and shopping centers also lack nighttime parking lot security, andthe most dangerous incidents occurring in public parks take place atnight.

Lights and cameras are typical devices deployed to improve security.Until the present time, society has paid for security with a highelectric bill resulting from keeping fixtures illuminated continuously.A second security precaution, video surveillance cameras, is added toact as a deterrent, but most cameras record for later review only eventsthat have already occurred. Fewer than 5% of surveillance cameras aremonitored; therefore, they do not proactively prevent crime.

Indoor incandescent lights currently use occupancy sensors or motiondetectors to automatically activate switching and thereby save energy.Unfortunately, these systems are ineffective in large, open outdoorareas. They work well indoors because incandescent lamps used to lightinterior spaces are capable of switching on and off quickly. Somefast-start fluorescent lights also switch sufficiently fast for indoorapplications. However, gymnasium lighting or lights used in large, openretail stores over long periods of time generally use gas vapor lightingto save energy. Unfortunately, gas vapor bulbs cannot be switched on oroff quickly, and they are difficult to dim effectively. Because they aretoo slow to switch on and off in response to real-time activity, theseexisting fixtures are incompatible with motion or occupancy sensors.

Most outdoor lighting for streets and parking lots also uses sodiumvapor or other gas vapor bulbs. These light sources are chosen formaximum efficiency because they require the least amount of energy.Typical sodium vapor lamps used in street lights have efficiencies ofabout 100-150 lumens per Watt. Low pressure sodium vapor lamps may reacheven higher efficiencies, up to 200 lumens per Watt, but they are seldomused because of the strong yellow cast characterizing their lightoutput, rather than the preferred white light. For this reason, somelarge area lighting applications, especially in locations like retailstores, have switched to metal halide lamps, because of their truerwhite light output. However, metal halide efficiencies are not so high,only about 80-125 lumens per Watt, and they have shorter lifetimes,which are the reasons why metal halide lamps are not used so often forstreet lights. Moreover, the above-mentioned efficiencies of metalhalide lamps and sodium vapor lamps are primarily achieved after thelamps are heated. When gas vapor lamps are cold, efficiencies and lightoutput are much lower, and ballasts required for these gas vapor lampsreduce efficiencies even further.

Motion sensors controlling indoor incandescent or special fluorescentlights typically employ either infrared or ultrasonic technology. Themost common indoor motion sensor is a low cost far-infrared detector,which is ideal for detecting human beings traversing a room. Infrareddetectors are also used in incandescent “security lights” near entrywaysor exits; however, when used outdoors, infrared detectors commonlyexhibit false triggering, as many security companies have discovered.Furthermore, the detection range of infrared detectors is limited, andthe detectors lose sensitivity as outdoor temperatures increase. Otherindoor occupancy sensors rely on ultrasonic detectors. An ultrasonicdetector transmits into a closed room sound waves at frequencies beyondthe range of human hearing. The detector then detects a shift infrequency by sensing reflected waves and comparing the transmitted andreflected frequencies. An object in the path of the sound wave moving ina direction toward or away from the sensor compresses the wave, therebyperturbing the frequency and introducing a “Doppler” shift. While theyare very sensitive to small changes within a closed room, like infraredmotion sensors, ultrasonic sensors do not recognize a target if it stopsmoving. Being highly sensitive, ultrasonic sensors are subject to falsetriggering by outdoor wind and air turbulence. Furthermore, because theydepend on reflections, ultrasonic sensors are unsuitable for use in wideopen or partly enclosed spaces, effectively restricting them to indoorenvironments.

Intelligent sensors for use outdoors in traffic control applications aregenerally unable to recognize moving vehicles or pedestrians along along stretch of road. The intelligent sensors cannot distinguish humanor vehicular motion from that of animals, newspapers blowing in thewind, parked cars, or a variety of other distractions. Even the mostsophisticated outdoor motion sensors, which are much more expensive thanthe indoor variety, may not distinguish between animals and humanbeings. Intelligent sensors may not detect moving vehicles sufficientlyfar away to turn on street lights soon enough, unless the vehicles aremoving very slowly. When cars are cold, for instance, upon ignition,infrared sensors have difficulty detecting cars located far away,because the sensors respond primarily to spatial temperature changes.

10 U.S. Pat. Nos. 7,045,968 and 6,909,921 describe indoor incandescentlighting control systems, including the use of motion sensors, in thelatter case. U.S. Pat. No. 6,151,529 describes an intelligent lightingcontrol system for indoor lights based upon analysis of data from simplemotion sensors. U.S. Pat. No. 6,114,816 describes a lighting system thatcontrols gas discharge lamps, dimming them automatically according toslow changes sensed in the immediate environment such as time of day andambient light level. Occupancy levels are mentioned, but primarily inreference to slowly changing occupancy. U.S. Pat. No. 5,986,357 featuresan occupancy sensor utilizing ultrasonic and infrared sensors, combinedfor use in indoor lighting control. U.S. Patent Application Pub. No.2005/0281030 for “Lighting Control Using LED Lighting with FluorescentLighting Fixtures” focuses on indoor applications and does not mentionimage or video sensors. What is needed, therefore, is a system for andmethod of preventing energy waste by intelligently controllingactivation and brightness of outdoor lighting so that lights remain ononly when they are useful, while simultaneously improving security inparking lots and outdoor public spaces.

SUMMARY OF THE DISCLOSURE

An intelligent lighting system employs energy-efficient outdoor lightingand intelligent sensor technology in cooperation with video analyticsprocessing to selectively illuminate outdoor spaces and to identify andevaluate events in a scene monitored by a video camera. The system thusfacilitates proactive and appropriate security responses to themonitored events, while saving energy by switching off lights when theyare not needed (e.g., when no people or vehicles are present).Intelligent lighting components of the system may significantly reducecosts of lighting-monitored areas such as streets, public parks, andparking lots, while simultaneously improving security, safety, andtraffic control. Energy savings afforded by a properly designed systemare estimated at 50%-90% of current usage, with a commensurate twofoldto tenfold increase in the lifetime of light sources, thereby savingmaintenance and replacement costs as well. Applications envisioned inthis disclosure focus on public thoroughfares or other roads andexpansive areas such as an interior of a large enclosure (e.g., aircraftassembly facility), an outdoor open space (e.g., a parking lot), and anoutdoor facility (e.g., a marina). Other large spaces expected tobenefit from an intelligent lighting control system include, forexample, vehicle transfer terminals, automobile dealerships, commercialwarehouses, hospitals, public works facilities, public parks, andcorporate manufacturing facilities.

Adding communication capability to an intelligent lighting systemenables transmission of a warning of approaching subjects to one orseveral lights farther down a street, allowing the lights to be moreresponsive. This communication may be wireless, or connections may useexisting power transmission infrastructure. For example, if a vehicletravels down a road at 50 miles per hour and is seen by a camerainstalled in an intelligent street lamp, the lamp relays to the nextstreet lamp down the road a message indicating the presence of traffic,prior to the arrival of the vehicle. This is useful on curved roads orin general to improve reliability of detecting approaching traffic. In aparking lot, when a subject is seen entering the lot, a sensor mayswitch on a nearby light while also alerting neighboring lights, so thatthe whole area remains lit as long as the subject is present.

An intelligent lighting control system may simultaneously enhance safetyand security in the areas where it is deployed. For example, intelligentimage sensors used to detect pertinent activity may also recognizetraffic problems, roadway accidents, or vehicles traveling in the wrongdirection. In parking lots, these sensors may recognize people loiteringaround cars, thieves attempting to break into vehicles, suspiciousindividuals approaching people emerging from a nearby building, or otherpotentially dangerous scenes. When combined with remote monitoring, suchsystems may prevent accidents and criminal activity, while enablingremote traffic control.

Additional aspects and advantages will be apparent from the followingdetailed description of preferred embodiments, which proceeds withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a representative overall intelligentlighting system installed in a parking lot and along adjacent roadways.

FIG. 2 is a pictorial perspective view of a preferred embodiment of anLED light fixture for an outdoor high-intensity light application suchas street lighting.

FIG. 3 depicts the light pattern produced on a road by the LED lightfixture shown in FIG. 2, when used in a street lamp configuration.

FIG. 4 is a pictorial perspective view of a preferred LED light fixturedesigned specifically for lighting parking lots or other large publicspaces.

FIG. 5 is a photograph of airport roadways and parking lots, illuminatedby lightposts configured with white LED fixtures of the type shown inFIG. 4.

FIG. 6 is a photograph of a visible/infrared sensor integrated circuitchip held over a person's eye to indicate scale size.

FIG. 7 is a display image of a parking lot intruder, contained within acomputer-generated rectangle indicating that a preferred video cameramonitoring system is capable of sensing motion within the rectangle.

FIG. 8 is a flowchart indicating the flow of information and controlamong components of a preferred embodiment of the intelligent lightingsystem of FIG. 1.

FIG. 9 is a photograph of a preferred embodiment of a network controllerthat can remotely manage and monitor the integrity of video datatransmission.

FIG. 10A and FIG. 10B are photographs of a central monitoring stationwhere video data may be screened by security guards for unusual eventsrequiring further attention. Some aspects of this function are automatedin the system disclosed, thereby reducing the need for securitypersonnel to engage in passive screening.

FIG. 11 is a photograph of a set of preferred video and audio equipmentintended for installation at remote monitoring locations.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 is an overall system block diagram of a preferred representativeintelligent lighting system 10. With reference to FIG. 1, major elementsof lighting system 10 include energy-efficient outdoor LED lightfixtures 12 illuminating a road 14 and a parking lot 16, optional audiospeakers 18, and multiple video cameras 20. Each video camera 20 (asindicated by an exploded representation of one of them at the bottom ofFIG. 1), is equipped with image sensors 30 for multi-directionaldetection of vehicles and for nighttime detection of human beings;programmable video analytics 32 capable of accurate motion detection,license plate recognition, and distance and velocity determination; anda programmable controller 34 managing audio speakers 18, image capturein cooperation with image sensors 30, and associated networkcommunications enabled by a network 36. Programmable controller 36 may,in the alternative, control the states of illumination of more than oneof light fixtures 12. Programmable controller 34 may includeself-diagnostic capability to detect failure of system components inresponse to information collected by one or more image sensors 30, videostreaming through network 36 to a remote central monitoring station 38that coordinates lighting system 10 and accommodates human interventionby security personnel, centrally initiated feedback control of audiospeakers 18 and light fixtures 12, and automatic local feedback control40 of light fixtures 12. Central monitoring station 38 in theembodiments described is part of a security or vehicle traffic controlterminal.

Although systems envisioned for streets and parking lots are nearlyidentical, their needs and requirements differ. Street lighting isprovided primarily for safety, while parking lot lighting existsprimarily for improving security. Both may benefit from the systemdescribed, but each application makes use of lighting system 10 indifferent ways. For instance, it may be desirable for street lighting torespond to moving vehicles, but not necessarily to pedestrians. In urbanor commercial locations, it may be beneficial to illuminate streets forpedestrians, but in more rural areas, it may be adequate to illuminate alength of road or highway only when vehicles are passing through it. Ina parking lot application, illumination of stationary vehicles may ceaseafter a period of time has elapsed, while lights turn on and remainilluminated in response to the presence of pedestrians.

Light Sources

State-of-the-art bright white LED lights suitable for use in LED lightfixtures 12 achieve efficiencies of approximately 130 lumens per Watt,which is comparable to efficiencies achieved by conventionalhigh-pressure sodium vapor lamps, most commonly used for street andparking lot lighting. The most significant energy savings, so faruntapped, can be achieved by taking advantage of the superior switchingresponse time of LEDs. Sodium vapor, mercury vapor, and metal halidelights are notorious for their slow switching speeds. It takesapproximately 5-10 minutes for such conventional light fixtures to reachoptimum light output, thereby precluding their use in an intelligentoutdoor lighting control application. A high efficiency LED lamp, on theother hand, switches from a nonilluminated state to a fully illuminatedstate in less than a millisecond.

While the efficiency of LED lights is expected to continue to increase,there are more compelling reasons for using LED lights. These include alonger life expectancy (50,000 hours versus 20,000 hours for sodiumvapor and 10,000 hours-15,000 hours for metal halide), better coldweather performance, reduced environmental impact (LED lighting productsare mercury-free), less-hazardous materials used in manufacturingcompared with levels of them used to manufacture high-pressure sodiumvapor and metal halide lamps, and the inherent directionality of LEDlight, which facilitates aiming light where it is needed. In residentiallocations where sudden switching and flickering lights may cause adisturbance, gradual dimming is preferred. This is another advantage ofLED lighting over most gas vapor lamps, which are difficult to dim.

LED light fixtures 12 suitable for large-scale use outdoors can beobtained from CREE Outdoor Lighting, Inc. of Durham, N.C. Each lightfixture 12 shown in FIG. 2 is in the form of a chevron and includes twogroups 50 of three rows 52 of white LED lamps 54, with ten individuallamps 54 in each row 52. Each lamp 54 is attached by a connector 56 to,and wired through, a rectangular supporting backplane 58, the surface ofwhich is coated with a thermal barrier 60. Rectangular supportingbackplane 58 is angled at approximately 130 degrees along a midline axis62 to form two backplane half-sections that provide light fixture 12with its chevron profile and thereby allow wider illumination of thesurface of road 14.

Three rows 52 of LED lamps 54 attached to either half-section ofbackplane 58 are each different by design. FIG. 3 shows a directionalLED street lamp and a resulting composite illumination pattern 66extending along the length of road 14. An inner row 68 closest tomidline axis 62 comprises bare LED lamps 80 with a hemispherical profileto illuminate a near field area 82 of pattern 66 directly underneath amounted light source 84. A middle row 86 comprises oval profile LEDlamps 88 designed to illuminate at mid-range area 90 of pattern 66; andan outer row 92 comprises collimating optic LED lamps 94 designed toilluminate at a farthest distance 96 of pattern 66 from mounted lightsource 84.

FIG. 4 shows an alternative fixture configuration 100, comprising adense square grid 102 of LED lamps attached at one end to a supportingbrick 104. Fixture configurations 100 are preferably mounted in pairs onlight posts for illuminating expansive areas such as parking lot 16, acity park, or a large intersection such as the airport intersectionshown in FIG. 5.

Sensor Technology

Intelligent lighting system 10 includes, mounted at periodic intervalsalong road 14 and within parking lot 16, video surveillance cameras 20equipped with image sensors 30 as component parts, for the purpose ofdetecting vehicles and pedestrians. Video surveillance cameras 20 areideally mounted on the same poles as those supporting the light fixturesand share the same source of power. in a preferred embodiment, atraditional street lamp is replaced with a device contained in a singlepackage that includes an LED light and a camera equipped with videoanalytics. The camera and analytics components may not necessarily beincluded on every light pole, but perhaps, for example, on every thirdone. Detection of vehicles on roads and pedestrians in and aroundparking lots pose different challenges and require different types ofimage sensor technology. For instance, traditional cameras employed asimage sensors do not function well without external lighting and are,therefore, not suitable for monitoring parking lots at night. Becausemoving vehicles including motorcycles and bicycles are required by lawto use active headlights at night, they are easily recognized, even atlong distances. Whereas individuals, while they may be visible tomotorists if they are wearing reflective clothing, seldom carry anactive, detectable light source. Thus, a different solution is needed tosense the presence of pedestrians at night.

For the street application, intelligent lighting system 10 uses imagesensors 30 of various types that are capable of recognizing a movingvehicle at a distance sufficiently far away to turn on lights wellbefore the vehicle arrives at the location of the street lamp associatedwith a particular image sensor 30. A preferred embodiment specifiesultra wide dynamic range CMOS (complementary metal oxide semiconductor)image sensors because they tolerate bright light such as directsunlight, headlights, or reflections without causing the sensor to“bloom” or overexpose the rest of the picture. In particular, mega-pixelCMOS dual video sensors are preferred as street lighting detectorsbecause they offer higher resolution for longer-range detection inaddition to low-light sensitivity and ultra wide dynamic range. Enhancedlow light sensitivity, also characteristic of high performance CMOSsensors, may be achieved by selecting sensors with low internal noise,large pixels for gathering more light energy, low f-stop optics and, insome cases, with video post processing to improve the signal-to-noiseratio by canceling out internal noise. CMOS image sensors have theadditional advantage of low cost.

To address the parking lot issue, another type of image sensor 30 thatis capable of detecting pedestrians at night can be located nearbuilding exits or at parking lot entrances, where a few lights may becontinuously illuminated. Then the rest of the lot may be illuminatedwhen needed in response to detection of pedestrians in these outerzones. In cases where light pollution is detrimental, for instance, ifneighbors prefer not to have lights flickering on and off during thenight, near-infrared light sources may be used, which are invisible tothe human eye but are easily detected by CMOS or CCD (charge-coupleddevice) image sensors. Infrared “lights” may be used primarily near theentrances to the lot, or they may be positioned to cover the entire lot.However, full coverage, while providing better security, wastes energyjust as continuous visible light does. Therefore, this approach is notideal.

One solution is the use of infrared image sensors 30 in cooperation withvideo analytics 32. The infrared image sensors control the states ofillumination of light sources by maintaining them in a nonilluminatedstate and activating one or more of them to an illuminated state inabsence of and in response to, respectively, an occurrence of a behavioror an event detected by performance of video analytics processing.

Another solution is to use far infrared image sensors to detect thepresence of pedestrians by measuring heat radiated from the human body.Far infrared sensors readily detect human beings in pitch dark with noexternal light; however, they are expensive. A preferred solution, inthe case of parking lots, is the use of image sensors 30 a (one shown inFIG. 6) that are capable of detecting short-range infrared light, suchas those developed by NoblePeak Vision Corporation of Wakefield, Mass.Near-infrared image sensors 30 a do not need an external light source tofunction at night because they use available short range infrared lightfrom the atmosphere as a source of ambient light. This makes them idealfor detecting human beings entering or leaving a parking lot, regardlessof direction. For example, near infrared image sensors 30 a may detectan intruder jumping a fence to avoid entrances, as shown in FIG. 7.While sensors 30 a are more expensive, the fact that they require noexternal lights saves enough money in reduced equipment costs and energyexpenditures to recoup within one year the cost of a more expensiveimager.

Video Analytics

Simply turning lights on and off as pedestrians enter and leave parkinglots gives a visual indication that the area is being monitored andprovides an important deterrent. After image sensors 30 confirm thepresence of vehicles or pedestrians, video analytics 32 can sense andanalyze their motion in greater detail. Security in parking lots, parks,and other public spaces may improve significantly when cameras equippedwith video analytics 32 are employed. This is so because video analytics32 processes video images in real time and thereby enables either animmediate automatic response or quick intervention from centralmonitoring station 38. When suspicious activity or threatening behavioris recognized by video analytics 32, automated, prerecorded voiceannunciation through audio speakers 18 may also be triggered to alertpeople in the area that parking lot 16 is being monitored for everyone'ssafety.

One suitable implementation of video analytics 32 is a Model No.VIQ-800HD video analytics product, which is available from VideoiQ, Inc.of Waltham, Mass., the assignee of this patent application, and theoperation of which is described in U.S. Patent Application Pub. No.2005/0002572 A1. The Model No. VIQ-800HD is capable of recognizingvehicles and human beings with a high degree of accuracy, despiteminimal processing requirements. Video analytics 32 has even greateradvantages when used with mega-pixel imagers, offering better processingefficiencies compared to traditional pixel-differencing approaches.Although this implementation of video analytics 32 is preferred, anothervideo analytics technology may be substituted, provided it has theability to ignore background lighting changes resulting from lightning,weather, flickering street lights, vehicle headlights, sunlight,reflections, animals, or leaves or papers blowing in the wind and torecognize the direction and speed of travel of pedestrians and vehicles.Video analytics processing of image data acquired by image sensors 30detects behavior or an event that includes motion or motion of a blobwithin the field of view of video camera 20 or recognizing a predefinedobject and tracking its movement.

As a specific example, it is desirable for video analytics 32 todistinguish between approaching and departing vehicles. Therefore theanalytics scheme preferably is capable of estimating vehicle speed,distance, and direction of travel. Early detection of approachingvehicles preferably allows enough time to turn on light fixtures 12,even with fast moving traffic. Video analytics 32 offers anotheradvantage in that it automatically calibrates vehicle distances byrecognizing typical distances between headlights for most vehicles andby observing traffic patterns. This is important in determining when toturn on light fixtures 12 in response to vehicle distance and speed.

After a vehicle has passed, light fixtures 12 may begin turning offimmediately, unless another vehicle is approaching. In the case ofstreets with two-way traffic, the preferred solution is to use two imagesensors 30, one surveying each direction. An alternative solution is touse a mega-pixel CMOS image sensor 30 a containing optics in the form ofmirrors and lenses to provide an extreme wide-angle view, allowing roadsin both directions to be covered by a common sensor. A single sensorusing mirrors and lenses may even provide a view of two perpendicularroads converging at a four-way intersection, rather than using fourseparate sensors.

Response, Network Control Functions, and Self-Diagnostics

Lighting, sensor, and video analytics technologies described above, ascomponents of intelligent lighting system 10, cooperate to operate lightfixtures 12 according to a decision tree, an example of which is shownin FIG. 8. At the core of the decision structure, programmablecontroller 34 (shown in FIG. 9) remotely activates or dims lightingaccording to information provided by video analytics 32, switchingstreet light fixtures 12 on in response to CMOS image sensors 30 a whenvehicles are detected traversing those streets, and switching them offwhen there is no traffic present. Similarly, programmable controller 34switches lights on in parking lots in response to IR image sensors 30 awhen people are detected leaving nearby buildings or when they enter alot from an outside road. Light fixtures 12 are then turned off aftersubjects of interest have left the area.

Components of system 10 also cooperate in communicating video andtraffic information through communications network 36 to centralmonitoring station 38, as well as self-diagnostic information useful formaintaining proper operation of overall system 10. A central monitoringstation 38, such as the Virtual Sentry intelligent security serviceavailable from ViSentry of Paramus, N.J. and shown in FIGS. 10A and 108,provides continuous intelligent control and review of real timemulti-camera and sensor data. Intelligent control enabled by the use ofvideo analytics 32 and programmable controller 34 relieves the client ofa traditional, passive surveillance role, in which operators are subjectto boredom and fatigue and can only respond to security breaches insteadof actively preventing them.

Within just a few seconds, a security guard located at a centralmonitoring station 38 may view a video clip and determine whether it isworth watching further. Active surveillance technology allows multipleparking lots to be effectively supervised by one guard, making realsecurity protection for outdoor spaces cost effective. Guards on dutyneed not wait and watch endless streams of real time video until theyfind something happening, a tedious observational task for which humanbeings are ill-suited. With video analytics 32, guards may beselectively alerted when something important or suspicious occurs thatis worthy of their intervention, that is, when human attention is usedto its fullest value. Behaviors or actions that video analytics 32recognizes as worthy of attention from security personnel include thefollowing examples: individuals loitering in a parking lot, an intruderentering the lot by jumping a fence, one person approaching anotherperson, a thief attempting to break into a car, someone hiding behindcars or behind other objects in the lot, vehicles parked in one placetoo long, an individual fleeing from a scene, a person waiving his handswildly and yelling.

Central monitoring station 38 provides redundancy and a backup database130 with a secure video/audio archive 132. Operators may respond toalarms by communicating with remote devices such as those shown in FIG.11, viewing multiple sites on a split screen 134, controlling videocameras 20, sending video snapshots by electronic mail, and creatingvideo clips of an alarm event. Most important, live video and videoclips of activity may be streamed to monitoring stations when videoanalytics 32 detects an event of concern. This technology brings humanattention to the scene, coupled with two-way voice communication,alerting a guard to respond to the situation.

In addition to energy savings and enhanced security, video analytics 32used in an intelligent lighting system 10 may improve traffic control onroads and streets because the system recognizes throughout the day andnight, for example, traffic jams, accidents, vehicles traveling thewrong way, and vehicles illegally parked. The same image sensors 30 andvideo analytics engine 32 used for energy savings and security mayprovide superior traffic information, by counting vehicles, monitoringspeeds of travel, and controlling traffic signals. Because mounted lightsources 84 are spaced fairly close together, it is easy to repeat weaksignals and transmit information over long distances. Wirelesstechnologies based upon Wi-Max or Wi-Fi and mesh communicationtopologies may be added inexpensively, expanding network 36 to create acitywide network. This approach is especially appealing if such anetwork is to be used for other city applications. System 10 may streamvideo content to traffic personnel located at central monitoring station38 or through a city traffic network to another remote station to allowimmediate observation of a traffic obstruction. A preferredcommunications approach for traffic control is via electrical powersupply lines, using power line communication technologies. This approachincurs the lowest additional cost, while electrical noise associatedwith street light power lines is typically low, making them idealforcarrying communications. Light fixtures 12 may also be hard-wiredusing traditional networking communications, such as Ethernet overcopper wire, or over fiber optics.

A preferred embodiment of intelligent lighting system 10 not onlycommunicates sensing data to remote central monitoring stations 38, butsystem 10 also downloads new algorithms for expanding recognitioncapability and for programming new detection criteria. For example, itmay be desirable to incorporate license plate recognition during anAmber Alert, targeted for a specific license plate number, or rules maybe added to recognize approaching police or emergency vehicles tocontrol traffic signals thereby allowing emergency vehicles to passfaster through intersections. A preferred system embodiment may alsocommunicate self-diagnostic information. For instance, if camera 20 hasbeen damaged or fails to detect motion, or if light fixtures 12 fail toswitch on or are not illuminating the area properly, the system is ableto sense the damage and alert an operator in central monitoring station38.

A camera 20 combined with video analytics 32 performs these diagnosticroles automatically, saving the need for manual maintenance checks. Forinstance, the system indicates loss of video data by detecting theabsence of the proper video signal voltages. The system can also detectwhen a camera 20 is out of focus by measuring frequency ratios in thevideo data, a lack of high frequencies indicating an out-of-focus state.A shift in the image itself indicates the camera 20 has been moved. Amotion estimation function can indicate also whether a camera 20 hasbeen moved, if most of the pixels are moving together in the samedirection, or whether there is a sudden change in traffic patterns.Another self-diagnostic function recognizes when video data have notchanged over an abnormally long time interval such as a full day, orwhen motion or light intensity levels differ from historical motionpatterns. These are indications that the video camera 20 is being maskedor otherwise blocked. In general, video analytics 32 can compare videodata samples to what is normal or expected at a particular location.

It will be obvious to those having skill in the art that many changesmay be made to the details of the above-described embodiments withoutdeparting from the underlying principles of the invention. The scope ofthe present invention should, therefore, be determined only by thefollowing claims.

What is claimed:
 1. An illumination system, comprising: a first lightsource configured to illuminate a first area of a location; a firstimage sensor configured to acquire mega-pixel resolution image datacorresponding to the location; video analytics configured to detect anevent in the location using the acquired mega-pixel resolution imagedata and to provide information about the detected event; and acontroller configured to direct the first light source to assume oneextended illumination state among a plurality of extended states ofillumination in response to the provided information about the detectedevent, the plurality of extended states of illumination including anon-illuminated state and a fully illuminated state.
 2. The illuminationsystem of claim 1, wherein the video analytics is further configured todetect a blob using the acquired mega-pixel resolution image data, theblob representing a group of pixels within the acquired mega-pixelresolution image data identified as related by the video analytics. 3.The illumination system of claim 2, wherein the video analytics isfurther configured to determine a distance from the first image sensorto the detected blob using the acquired mega-pixel resolution imagedata.
 4. The illumination system of claim 3, wherein the controller isfurther configured to direct the first light source to assume thenon-illuminated state until the determined distance of the detected blobsatisfies a predefined threshold distance.
 5. The illumination system ofclaim 2, wherein the video analytics is further configured to determinea speed of the detected blob using the acquired mega-pixel resolutionimage data.
 6. The illumination system of claim 5, wherein the speed ofthe detected blob determines a timing of when the controller directs thefirst light source to assume the one extended illumination state.
 7. Theillumination system of claim 1, further comprising: a video cameracomprising the first image sensor, the acquired mega-pixel resolutionimage data corresponding to a field of view of the video camera.
 8. Theillumination system of claim 7, wherein the video camera includes one ormore additional image sensors configured to detect electromagneticradiation at wavelengths outside of the visible spectrum.
 9. Theillumination system of claim 7, wherein the video camera includes thevideo analytics.
 10. The illumination system of claim 1, wherein thevideo analytics is further configured to distinguish between backgroundlighting changes in the first area.
 11. A light fixture, comprising: afirst light source configured to illuminate a first area of a location;and a lighting controller operatively coupled to the first light sourceand configured to direct the first light source to assume one extendedillumination state among a plurality of extended states of illuminationusing light control signals in response to information received from avideo analytics over a communication medium, the plurality of extendedstates of illumination including a non-illuminated state and a fullyilluminated state, the received information associated with eventsdetected by the video analytics using mega-pixel resolution image datacorresponding to the location acquired by one or more image sensors. 12.The light fixture of claim 11, wherein the lighting controller isfurther configured to direct the first light source to assume thenon-illuminated state until the received information indicates the videoanalytics has detected an event in the location using the acquiredmega-pixel resolution image data.
 13. The light fixture of claim 11,further comprising: a second light source to illuminate a second area ofthe location, the first and second areas being different areas of thelocation, the light fixture being configured to provide compositeillumination patterns, the first area being a near field area of thecomposite illumination patterns and the second area being a far fieldarea of the composite illumination patterns.
 14. The light fixture ofclaim 13, wherein the composite illumination patterns change over timein response to a direction of travel corresponding to a blob detected bythe video analytics using the acquired mega-pixel resolution image data.15. The light fixture of claim 11, wherein the communication medium is apower line, a wireless communication link, a wired communication link,or a combination thereof.